BROCKTON – Mayor Bill Carpenter was scheduled to announce his plans for the future leadership of the Brockton Police Department on Friday during a press conference, but first he'll have to argue for those plans in court.

Carpenter was expected to announce his pick to succeed Police Chief Emanuel Gomes, who is returning to his former rank of captain on Friday, after a deal allowing him to do so was agreed to by Gomes, the city of Brockton and the Police Supervisors Union last week.

On Wednesday, however, the union filed a request for injunction in Brockton Superior Court to block Carpenter from appointing Robert Hayden, Carpenter's public safety adviser during the campaign, as interim chief.

A hearing has been scheduled for 2 p.m. on Friday to determine whether Carpenter is allowed to appoint Hayden to the position.

Last week, Carpenter filed an ordinance with the City Council seeking to replace the position of police chief with a civilian police commissioner.

Carpenter has also indicated that if the ordinance passes, he intends to appoint Hayden to the new position.

The ordinance, however, will not pass before Gomes steps down on Friday. That led to speculation that Hayden would be appointed as interim chief. But the police union is now arguing that if Carpenter places Hayden in the position it would be illegal.

The argument centers on a Massachusetts law mandating that police officers retire at 65.

For Hayden to fill the interim chief's position, he would have to be a sworn police officer. But Hayden, who is 71, would be prohibited from joining the force due to his age.

It is unclear, however, what options are available to Carpenter when he argues against the injunction in court on Friday.

"I'm not privy to what the mayor can do, but if he goes through with it (the appointment), he has to accept what may happen if the court decides against him," said Michael Kryzanek, the executive director of the Minnock Center for International Engagement at Bridgewater State University.

While Kryzanek added that Carpenter has a right as mayor to fill the position with the person he wants, the appointment could come with a cost.

"All of this creates a problem for Mayor Carpenter that certainly isn't going to go away within a day," Kryzanek said. "It shows that the mayor has created a storm of controversy early on that probably could have been avoided."

Kryzanek compared how Carpenter has handled the situation with that of of Boston's new mayor, Marty Walsh, who appointed new leadership at his police department after taking office.

Page 2 of 2 - "If you look at Mayor Marty Walsh, he brought his chief and commissioner up from within the ranks. He didn't go from the outside," Kryzanek said.

The Boston Police Department has a structure in which a superintendent-in-chief is second-in-command to a police commissioner.

If Hayden is appointed as interim chief or commissioner, he would be the first outsider selected to head the department in 40 years.

The last Brockton chief to be appointed from outside the department was Robert Galatti, a former captain with the New York City Police Department, in 1974, said Ward 4 Councilor Paul Studenski.

Studenski, who is a former Brockton police chief himself, added that Galatti was also a professor at Northeastern University at the time he was hired and a former commanding officer in the police academy.

According to Gallati's 1996 obituary in the New York Times, he also developed the computerized system of fingerprint identification which would become the model for the FBI's system today.